Would there be any degradation in SQ if I replace the 47.5K input-load resistors with 100K or 150K resistors? I ask because each preamp channel will be driving two F4 channels plus a 67K-input channel of a subwoofer amp for a net of 17K-odd Ohms. That moves the filterpoint of the preamp's output-coupling cap to about 4.5Hz, about an octave higher than I'd like, and I prefer not to have to buy and install more expensive Teflon-film caps.

I know you're a busy man, but perhaps you didn't see this, and I'd really appreciate your help:
1. Would it make sense to replace Cs 1 and 2 (in new-to-me, FW-manufactured-last-fall amps) with something like BlackGates?
2. Could they be any smaller…say 100uF or 150uF…and still work correctly? I have plenty of 100uF BGs so I could make them all (8 caps in 2 amps) 200uF caps.

Wowwa, cool, go for it dude!!!
But?
That's all???
Hey, I don't suppose I'm hi-jacking if:
I propose 1A minimum/Comp. FET Pair???
How about if we dump the Fairchild/IRF devices and go to 2SK1530/2SJ201???
Along with that, we should just put those Rs in the right area with .2-.22??? .1-.15 if you have balls(eggs-huevos, or matched FETs etc.)???
I suppose we need to work on that TL thingy for proper bias???
So do you want classA?// We'll Lower the 24V rails to 19-21V rails??? (a 15-0-15 0r 16-0-16 xfmr)...
I just thought those would be improvements???

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